Bitter Coffee: Why It Happens and How You Can Brew Better

 

We’ve previously talked about coffee being brewed too sour, and the different reasons why the brew possibly ended up the way that it did. Today, we’re talking about the opposite end of that spectrum and looking at how coffee ends up being bitter. It’s not a big surprise that the vast majority of people would associate coffee being this bitter brew. Despite its reputation as being a bitter beverage, the reality of it is that coffee has many more complex and wonderful notes that get covered by the bitterness that comes from a myriad of different factors. Let’s take a look at them, shall we?

The Coffee Is Over-Extracted

Coffee is extracted in 3 phases: first are the sour notes, then the sweetness/complex notes, and finally the bitter notes. If your brew time is too long, you might end up getting to that third phase when the only thing left to extract are the bitter notes of the coffee. Your brew time for pour overs should be around that 3-minute mark, though if you’re still finding it bitter, you can try to cut that in 15 second increments.

Check Your Grind Size And Grinder

 

When your coffee is ground on the finer side, it will extract faster, meaning it will also get to that bitter phase a lot faster as well. You’ll want to make sure your coffee is ground to that sweet spot that feels like kosher salt, not too coarse and not too fine. When you find that sweet spot, it should also help to improve your brew time since it will allow the water to pass through the coffee easier. Another tip is to check your grinder if it’s in need of a cleaning, since it not only earns a build-up of ground coffee, but it’s probably the one piece of your home brewing gear that you might forget to clean.

The Water’s Too Hot

When your water’s temperature is too hot, it can overcook your coffee. When you’re brewing in a normal temperature environment, you won’t need to consider raising the temperature of your water to account for a cooler climate, so that 90-94 degrees Celsius temperature should be fine. You don’t want to have your water be at boiling and higher since this will definitely get your coffee’s bitter notes out from more than just over extraction.

The Coffee’s Roasted On The Dark Side

Darker roasted coffees are typically meant for those looking for fuller bodied coffees, or to pair in a milky beverage. They’re characteristically on the bitter end of the spectrum as well because as they’re roasted for longer, the compounds in coffee that would typically represent acidity get converted into bitter tasting compounds. You can also think of it like grilling a steak, where if you overcook it, you end up burning it.

The Coffee’s Stale

One that seems to often get missed out, but you’d be surprised how often this results in a bitter brew. Coffees that have become stale end up tasting bitter because it’s at that point where a good chunk of the CO2 inside the beans have already depleted. As a result, when you brew, it extracts or gets to the bitter part much faster. If you’re able to consume a bag of coffee within a month of its roast date, that should be good.